This invention relates to a contacting arrangement for mass transfer operations comprising plates which are particularly vertically oriented and are parallel and equally spaced apart.
U.S. Pat. No. 4,107,241 discloses a contacting arrangement for mass transfer operations comprising superimposed louverlike grates, which are angularly offset and extend transversely to the direction of flow through said arrangement. Each of said grates consists of oblique strips and of connecting elements, which are parallel to themselves and transverse to the oblique strips. Such a contacting arrangement has desirable properties regarding its mass transfer-promoting activity and its hydraulic activity and the pressure loss caused by it. On the other hand it has been found that the assembling of the components involves high manufacturing costs.
It is an object of the invention to provide for mass transfer operations a contacting arrangement which can be manufactured at lower costs, particularly at lower labor costs.
Another object is to provide such a contacting arrangement which has a stronger mixing activity so as to most strongly promote the mass transfer.
In order to accomplish these objects, a contacting arrangement for mass transfer operations comprising vertical plates which are parallel and equally spaced apart is improved in accordance with the invention in that each of the plates is formed with slots, which are arranged in vertically spaced apart rows, the longitudinal directions of the slots in adjacent rows are inclined from the vertical in opposite senses, and each of said slots is defined by at least one lug, which is bent from the plate at right angles thereto. Adjacent tongues associated with a row of slots are preferably bent to mutually opposite sides of the plate. Each slot nay be defined on opposite sides of the slot by two of said lugs, which are bent to opposite sides of the plate, preferably at right angles to the plate. The lugs may be bent in arcuate shape on a radius or at an angle, particularly a right angle, from the plate.
Such a contacting arrangement has particularly desirable hydraulic and other properties. The plates can be stamped in one operation and can then be assembled by crossties or other known means to form the sets. To control the width of the plates, a continuous strip which leaves the press may be cut to desired lengths by means of plate shears. The sets of plates held together by crossties can readily be placed on conventional carrying grates in the columns. On these sets of plates placed on a grate, upper sets of plates are placed, which extend at an angle to the next lower set of plates.
Having slots which have preferably the configuration of narrow upright rectangles and are defined by lugs bent to opposite sides of the plate in alternation, the plates may be so arranged that the slots in corresponding rows of adjacent plates are inclined in opposite senses and the inclined lugs which abut each other between the plates form mixing and turbulence-generating nips for the flowing fluids. The flowing liquid or gas stream is divided at each of the crossings of aperture-defining lugs of adjacent plates and the mixing and turbulence-generating nips formed by said lugs result in a considerable improvement of the mass transfer. The oblique slots and the lugs defining them have suitably an inclination of 15 to 45 degrees from the vertical.